Hydrothermal Carbonization as Sustainable Process for the Complete Upgrading of Orange Peel Waste into Value-Added Chemicals and Bio-Carbon Materials

In this study, a simple and green protocol to obtain hydrochar high-added value products, mainly 5-hydroxymethylfurfural (5-HMF), furfural (FU), levulinic acid (LA) alkyl levulinates, by using the hydrothermal carbonization (HTC) of orange peel waste (OPW) is presented. Process variables, such as reaction temperature (180–300 °C), time (60–300 min), biomass:water ratio initial pH were investigated in order find optimum conditions that maximize both yields solid 5-HMF levulinates bio-oil. Data obtained evidence highest yield at 210 °C temperature, 180 min residence time, 6/1 w/w water 3.6 pH. The bio-products distribution strongly depends on applied conditions. Overall, was found be best maximizes production presence pure medium.